Process of distillation.



PATENTED DEC. 11, 1906. B. A. LE SUEUR.

PROCESS OF DISTILLATION APPLICATION FILED IAR. 11. 1901.

UN [TED STATES PAT...]NT OFFICE. ERNEST A. 'LE SUEUR. or SAULT s'rn MARIE, ONTARIO. CANADA.

PROCESS OF DISTILLATION.

Specification of Letters Patent.

Patented Dec. 1 1. 1906.

To all whom it may concern:

Be it known that l; ERNss'r A. [in Suave, a subject of the King of Great Britain, residing at Sault Ste. Marie, in the Province ol" Ontario, Dominion. oi" Canada, have invented certain new and useful Improvements in Processes of- Distillation, of which the following is a specification.

-My invention has for its object to enable evaporation and subsequent condensation to be effected with a minimum expenditure of heat. It utilizes the liberation of latent heat of vaporization of matter already vaporized and whose pressure has been raised subsequently to its becomingvapor to bring about absorption of latent heat by a suc cessive portlon of the same matter in the act of becoming va or. 'I utilize the heat content of the con ensed vapor to efiect a preliminary raising of the temperature of the said liquid.

Assuming a typical casesuch, for instance, as the distillation of water from an impure liquid mixture which exists to start with at ordinary temperatures, my process is carried out as follows: I pass the said liquid conveniently or at about atmospheric pressure'through a passage in a counter-current ap aratus, whereby its temperature is gradua ly raised to a pointat which boilin ocours. I withdraw the steam from the 0 amber in which it is being liberated and raise its pressure by an amountit may be two pounds or square inch-greater than that under w ich it was liberated. I then, main taining the higher pressure on it, return the vapor to contact with one side of the chamber, (or pipe system,) on the other side of which the aforesaid boiling is occurring. Therebyit is caused to condense 'to the liquid form and give up its latent heat of va orization to the mixture in the act of boiing in the said chamber. The hot condensed water I pass through a passage in the counter-current apparatus, so as to cause it to give upheat to the said ap aratus and its contents prior to being with rawn from thesystem. watt view to protecting the system from un'ned'estus auxiliary heatmay be needed to make sa lossesof heat the hot portions are lagged wit materials of low-heat-conductingpowers.

Auxiliary heat will be needed in starting the process, and, furthermore, under circumstances of its being necessary, for instance, to withdraw concentrated liquid directly from the high-temperature portions of the apparahereinafter described, so as to good the draft oi" heat occasioned thereby; but wherever it is not 'necessary to withdraw such coneentrated. liquid in a hot condition its heat will preferably be utilized by conveying it through an auxiliary passage in the eounter-eurrent apparatus prior to its witlulrawal from the system, whereby it is cooled. WVhere the conditions demand the application of auxiliary heat, the same may .conveniently be. applied by admitting'to the vapor (preferably, as a rule, the compressed vapor) auxiliary vapor from an external source.

Gases dissolved in the liquid to be treated may either be removed in large part prior to admission of said liquid to the system or they mayibe rejected from the vapor-spaces as, for instance, by blowing off a vaporous mixture containing them. This mixture may. also be conveyed down in temperature through an auxiliary passage in the countercurreixt apparatus prior to rejection.

In the above have spoken only of singleel'l'ect conceiitration, and this is usually all that it will be necessary to use. However, by compressing to a higher degree than is required [or single eil'ect we may obtain a plurality of cil'ects, as follows: The vapor withdrawn from the chamber in which boiling is occurring under the lowest pressure is withdrawn and compressed to a comparatively high degree. the condensing-coils or their equivalent, located in thermal communication with the contents of the chamber in which boiling is taking place under the highest pressure and the vapor fronrthis chamber admitted to the condensing-space pertaining to the chamber next below in pressure, and so on, in case the effect is more than double.

Referring now to the drawing, in which the mere principles involved are illustrated without any attempt at showing structural details, liquid to be concentrated is placed in the reservoir 21 and flows through the pipe 2, which constitutes one passage-of a counter-current apparatus, into the evaporatingan 3. It is there exposed to heat from t e coil 6, said heat bein derived, as e caused to boil. The vapor given off flows through the pipe 31 to the com ressor 4, in which it has lts pressure raised a suitable amount and from which it is delivered through the pipes.

It is then admitted toindicated on thegage 5. By its condensatlon under pressure in coil 6 and by the consequent liberation of latent heat it maintains the act of boiling of the liquid in the pan 3. The condensed vapor flows away through the pipe 1, Which constitutes a second passage of the counter current apparatus above mentioned, and, being brought into thermal communication with the current of liquid to be concentrated flowing in the opposite direction in the pipe 2, it is caused to We u its heat to'said current and arrive at t e ta 11 past the check-valve 12, which prevents false flow, in acool condition.

In starting the system live steam from an outside source imay conveniently be ad-' mitted past'the-valve 43 to the coil 6, so as initially to raise the temperature-of the li uid in 3. Thesame supply may. also be ma e use of during regular operation in case the heat losses are eater than the gains.

In starting, t e space above the liquid in the vessel 3 will usually be filled with air, and as it is undesirable to introduce such a large body of gas into the compressed-Va or spaces it will usually be preferable be ore starting the compressor 4 to cause boiling of the liquid in 3 by the admission of live steam to the-coil 6 and to blow ofi most or all of said air through the valve 32. In regular. operation, however, the latter valve will.

usually be'kept shut andrejection of the uncondensable gases in the vapor be accomplished through the valve 62. This valve permits egress of fluid from the low-temperature end of the pipe 61, which draws from the to of the coil 6. The va orous mixture of which said coil is relieve throu h said pipe 61 flows in counter-current to t e current of li uid from 21, ascending in temper-i ature, an a portion of its heat, including the latent heat of that portion of the contained vapor which condenses, is given up to said liquid. In the same Way hot concentrated liquid has its temperature-utilized where possible b being drawn away from the pan 3 throng the pipe 35 past the valve 36. The pipe 33 and the valve 34 give an alternative means of withdrawin the contents of the pan in the hot state w ere necessary.

Besides the parts shown the hot portions of the system will be thoroughly lagged with materials of low-heat-conducting powers to avoid unnecessary wastesof heat. 7

I am aware that the princi le of raising the latent-heat tential of steam by compressing it is wel known, and a notable, case in point is Ipatent to Faesch, dated January 25, 1881.

to been able to compete in economywith the owever, no such process has hitherprocess ad passage ina therma to promote the said boiling usual multi jle-effect evaporating-pans. My

d the feature of the eflicient utilization' of the sensible heat ofthe hot condensed water and of the -hot concentrated mother-liquors, as well as of both the latent and sensible heats of the hot vaporous mixture containing fixed gas, as air, which it is necessary to remove from the vapor-spaces.

What I claim is I 1. The process of effecting distillation of a substance from a liquid containing it which consists in conveying said liquid through a ratus, whereby its; tern erature is raise n causing it to iberate t e vapor of the said counter-current a pasubstance, in removing said vapor and suitably raising its pressure, in bringing said vapor into thermal communication with li uid in the act of 'liberatin vapor of the said substance so as to cause iquefaction of the vapor under the higher pressure and to romote liberation of vapor by the said iquid, in conveying the product of said liquefaction through a passage in a thermal counter-current apparatus, whereby it is gradually cooled, and, through another such passage, conveying the concentrated li uid residue from the evaporating cham er, whereby it also gives up its heat' to the incoming liquid, substantially as "shown and described.

2. The process of effecting distillation of a substance from a liquid containing it which consists inconveying said liquid mixture containing gas which has made itsappearance in the va or and conveying it t ough a assage in't e counter-current a paratus, W ereby it is gradually cooled, su stantially as shown an described.

In testimony whereof I' afix my signature. in presence of two Witnesses.

ERNEST a LE SUEUR. Witnesses G. A. HARcoURr, LEIF NISFEN.

ressure and through a passage in a thermal counter-current appara- 

